Alberto, The back focus problem is pretty well known in 10D circles. The only solution is to send the camera and the lenses into Canon's repair service. They can tweak the focus to bring it into spec. But that is all they will do: put each camera and lens into spec. They don't, as I understand it, tweak the camera to the lens. Many people indicate that there is still a problem even when the camera is up to proper specifications, but most have found happiness after the tweak (or so I understand from another list I monitor), The problem is due in part to the fact that Canon does not consider the 10D is a "professional" camera (it was never advertised as such). So the specs for focus is not necessarily as tight as a pro would want, although it is good enough for most amateurs. A camera can be "in spec" and still not be as good as you would like. The back focus problem is evidently real, although the vast majority of 10D's do NOT have the problem. If your brother expects and demands an absolute focus, he probably will have to move into Canon's pro line of cameras (the EOS 1D series). But sending the camera to Canon's national repair service (New Jersey or California) will probably help the back focus problem. peace rand
